No bighead or silver carp found during spring seasonal intensive monitoring

Chicago Area Waterway System intensively sampled during semi-annual monitoring

July 25, 2023

Contact:
Tim Patronski, Tim_Patronski@fws.gov, 612-418-9148

A 44 pound (22 kilogram) grass carp is weighed on a boat during the monitoring event
One grass carp was removed from Lake Calumet during seasonal intensive monitoring sampling. The fish, captured in a gill net by a contracted fisher, was approximately 44 inches long and weighed 44 pounds. Photo courtesy of Claire Snyder/Illinois Department of Natural Resources.

No bighead carp or silver carp were captured or observed in the Chicago Area Waterway System (CAWS) during two weeks of rigorous sampling conducted in May 2023 during the annual Spring Seasonal Intensive Monitoring (SIM) event. Partner agencies under the leadership of the Illinois Department of Natural Resources (IDNR) with support from the Invasive Carp Regional Coordinating Committee Monitoring and Response Working Group meticulously sampled hundreds of sites in the CAWS as part of this effort.

One grass carp was collected in Lake Calumet during sampling. Grass carp, another invasive carp species, are occasionally captured in the Lake Calumet area and are removed when encountered. The male fish was approximately 44 inches long and weighed 44 pounds. Blood, bone, and tissue samples were collected from the fish for further analysis.

Each spring and fall, an intense collaborative surveillance effort focused on detecting live bighead carp and silver carp takes place throughout the CAWS. The Spring 2023 SIM event was conducted May 15-26. Utilizing boat electrofishing, gill netting, and seines, teams from the IDNR, Illinois Natural History Survey, U.S. Army Corps of Engineers, and U.S. Fish and Wildlife Service, with the aid of contracted commercial fishers, monitored 807 sites throughout the CAWS.
In total, more than 75 hours of electrofishing were completed, 49 miles of gill net set, and almost two miles of seine were pulled. The densest sampling was conducted in the Calumet River and Lake Calumet, where a live silver carp was found on August 4, 2022. Further intensive sampling efforts will be conducted in the CAWS in October 2023.

For more information on the Invasive Carp Regional Coordinating Committee's comprehensive invasive carp management strategy for protecting the Great Lakes from Asian carp, please view the 2023 Invasive Carp Action Plan (9.3 MB PDF).

A contracted fisher in a boat pulls a smallmouth buffalo fish from the river using gill nets
An Illinois Department of Natural Resources-contracted fisher pulls a native smallmouth buffalo into the boat using gill nets while sampling for invasive carp in the Chicago Area Waterway System. Photo courtesy of Claire Snyder/Illinois Department of Natural Resources.